The Insect Methusalah: The Cicada
Do You Know?
What insect can make a noise louder than a rock concert, equal to a chain saw, and be heard up to half a mile away?
What insect lives up to 17 yrs. underground before emerging as an adult?
What insect buries itself up to 8 feet underground where it sucks on tree roots?
What insect emerges every 17 yrs. in plague-like numbers in the Eastern United States?
What insect is often fried up and eaten and called the “ground shrimp”?
Cicadas are one of the most interesting of all insects. They come in many varieties. There are more than 2,500 species world-wide. The only continent where they are not found in Antarctica. These insects are often called the insect Methuselah’s because of their longevity.
Now That’s Odd!
Some species can live up to 17 years underground before emerging as adults. These Cicadas are known as the Periodic Cicadas. Other Cicadas have one year annual cycles, 3 yrs. , or 13 yrs. cycles. Did you notice these numbers are all odd numbers? Scientists are not sure why but this seems to be consistent with all the species.
Where does the cycle begin? The female Cicada makes slits in the outermost twigs of tree branches. She then inserts her eggs. One female can lay up to 600 eggs. About 6 weeks later when the nymphs come out of their egg cases they fall to the ground and begin digging. They can dig up to 8 feet underground to find the juicy roots of trees from which they feed. Their long needle-like mouth-parts stab into the roots from which they extract a constant flow of sap. Depending on their species, they can stay underground for a year or up to 17 years (the Periodic Cicadas). Once they burrow their way back up to the bases of tree trunks, they climb up and split their nymphal skins down their backs and crawl out as adults. This old skin remains attached to the tree. When they first emerge their wings are all crumpled up, but after a few hours they pump up their wings and dry them out and become strong fliers. They then go to the tops of the trees where they spend the adult portion of their lives. This is a short period of time compared to that underground. Usually they are adults for only 5-6 weeks if they survive the many predators that feed on them.
Who Eats Cicadas?
Cicadas have many enemies that feed on them. These include: birds, many kinds of rodents: like squirrels, moles, mice, and rats. Other mammals, like bats, also feed on them. Lizards, and even fish will eat them. Believe it or not, even people eat them! Ever heard of stirred fried Cicadas? About every 17 years when the Periodic Cicadas of the Eastern United States emerge, many restaurants will offer special meals of Cicadas prepared by some of the finest chefs of the world. I have never tried them, but some people call them “ground shrimp”. They usually fry up the nymphal stage when they emerge in large numbers.
If you hear the noise of the Cicadas you are hearing the males. They have special noise boxes, that are similar to drums, on the sides of their abdomens. These structures are known as “tymbals”. They make noises to attract females as well as other sounds to warn other males to stay out of their territory. Each species has its own unique sound. They can collectively create the noise up to 110-120 decibels. That is equivalent to that of a chain saw, or a rock concert! That’s a lot of noise! Interestingly, if you hold a live male in your hand it will often make this sound to try to scare you away. It is amazing how God designed these insects so they could emit such a loud sound.
Hard to Locate
You would think that anything that made that much noise would be easy to locate. Believe it or not, it is not easy to locate a singing Cicada. This is partly due to the fact that more than one of them are singing at the same time.They are a lot like ventriloquists that seem to send their voices elsewhere. I once heard a Cicada and was only about three feet away and didn’t see it until it moved. The sound seems to come from everywhere at the same time. It’s interesting that the females can distinguish where the males are and find them quickly even when their are several different species in the same location. They can find their mates and reproduce their young. This is the primary purpose of adult Cicadas.
The Better to See You
As you can see in the above photo, Cicadas have two large compound eyes on the sides of their heads. In addition, they have three small simple eyes right in the middle of their heads. If you look closely, you will also notice that they have a tiny pair of antenna. Their legs are jointed and they have claws on the ends of their feet with which to grasps branches and the bark of trees. Look closely, you may also see the long, needle-like mouth tucked up under their belly. It looks a lot like a bird’s beak. These sometimes are up to a half inch long.
Not Harmful to Man
Though they might look menacing, they actually cause no harm to man. They are very interesting to examine up close.
I recall one summer while serving as a camp counselor in Northern California. I heard a cry coming from the mountain top where summer campers were sleeping in a large Teepee. One of the girls woke up and saw a monster crawling up the side of her tent. Because the light from the outside came through the cloth the image of an emerging nymph was magnified and appeared to be many times its actual size. It really did look scary from the inside of the tent. Once I removed it and showed it to the girl and her tent- mates and explained that it was harmless, all again was calm on the hill.
Cicadas belong to the insect order Homoptera. This term means “same wings”. The Cicadas have one large pair of wings and one smaller pair. The smaller pair are one half as large as the front pair. Their wings are transparent and veined. Other members of this order include the aphids, tree hoppers, and leaf hoppers.
Cicadas are covered with a waxy coat that helps shed water. Their wings also are hydrophobic, and repel water. This is a good thing for the Cicadas because they often live in very moist places. It also keeps their wings ready for flying when necessary to avoid predators or find a new location. God gave these insects everything they would need to survive.
One of the most amazing things about Cicadas is the vast numbers that can emerge in a matter of weeks! The Periodic Cicadas of the Eastern United States, which emerge every 17 yrs., can come out in numbers that equal up to tens of thousands to 1.5 million insects per acre. That is like the Biblical plagues of the Old Testament times. In these numbers they can be a nuisance, getting squished on the pavement, covering branches of trees and sidewalks. These vast numbers provide a feast for many animals that take advantage of their appearance. In just a short while all of the remnants of these creatures will be gone, eaten and recycled. Their bodies provide nutrients for the soil and food for many fungi and bacteria in the soil.
Now It’s Your Turn to Take Time to Look at and Study Them!
So….the next time you encounter a Cicada, take time to take a closer look. They are marvels of design and very interesting to observe. The closer you look the more amazing they are. They definitely demonstrate the marvelous design of their Creator.